1. Field of the Invention
The present invention relates to a liquid-crystal display device, a defective pixel examination method for use with the liquid-crystal display device, a defective pixel examination program, and a storage medium, and, more particularly, relates to the examination of pixel defects.
2. Description of the Related Art
In recent years, display devices have rapidly become thinner, and, for example, liquid-crystal devices (LCDs) have become widely popular. Since such liquid-crystal display devices feature a low profile, a low weight, and a low power consumption, their use in so-called mobile terminals, such as, in particular, mobile phones, personal digital assistants (PDAs), notebook personal computers, and portable TVs, has increased. Furthermore, liquid-crystal display devices have begun to be used in rear projectors, front projectors, and the like.
Among such liquid-crystal display devices, an active-matrix liquid-crystal display device has become dominant. An active-matrix liquid-crystal display device is structured in such a manner that a substrate having transparent pixel electrodes and thin-film transistors (TFTs) arranged thereon, and an opposing substrate having one transparent electrode formed on the whole display section are provided, and these substrates are disposed to oppose each other with a liquid crystal sealed therebetween. By controlling the TFT having a switching function, a voltage corresponding to a pixel gradation (hereinafter referred to as a “gradation voltage”) is applied to each pixel electrode, and an electrical potential difference between each pixel electrode and the electrode of the opposing substrate is generated, thereby changing the transmittance of the liquid crystal and enabling the display of an image.
On the substrate having TFTs arranged thereon, a plurality of data signal lines for applying a gradation voltage to each pixel electrode and a plurality of gate signal lines for applying a control signal for switching the TFTs are arranged. Application of a gradation voltage to each pixel electrode is performed via data signal lines, and during one frame period for image display, application of a gradation voltage to all the pixel electrodes connected to the data signal lines is performed, thereby enabling the display of an image on the liquid-crystal display section. The gradation voltage applied to each pixel electrode in this manner is held by the capacitive element (capacitor) provided in the output electrode of each TFT until a gradation voltage is next applied.
Such liquid-crystal display devices have commonly been of a transmission type, but recently a reflection-type liquid-crystal display device, such as a liquid-crystal-on silicon (LCOS) display device, has begun to be introduced to the market. For this LCOS, since a silicon wafer can be used as a substrate, transistors with a higher performance than that of transmission-type transistors, whose circuits are formed of polysilicon on a glass substrate, can be used.